Feeding device for grinding-machines.



J. S. WlLCOX, 1a., A. TURNER & H. W. DUNBAR. FEEDING DEVICE FOR GRINDING MACHINES.

APPLICATION FILED JUNE 28.19I5- 7 1,197,700. PatentedSept. 12, 1916.

2 SHEET5SHEET I.

I I 1 NK Z 25' L I II IIIIIIIIIIIII IIIIIIIIIIE 7%272665 J. S..W\LCO-X, 1a., A. TURNER & H. 'W. DUNBAR. FEEDING DEVICE FOR GRINDING MACHINES.

I APPUCATION FlLED JUNE 28,19i5. 1,197,700. Patcntvdbvpt. 12,1916.

2 SHEETS-SHEET 2 nummmu 5 1 MIo-rngp STATES PATENT OFFICE.

JOSEPH s. wILCox, JEL, 0F ATH'OL, AND ALBERT TURNER AND HOWARD w. DUNBAR, OEwoE Es'rEn, MASSACHUSETTS, ASSIGNORS TO NORTON GRINDING COMPANY, OF

WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

FEEDING DEVICE FOR GRINDING-MACHINES.

To (ill whom it may concern Be it known that we, JOSEPH S. WILCox,

J r., ALB RT TURNER, and HOWARD W. DUN- BAR, citizens of the United States, said W11."-

cox residing at Athol, in the county of Worcester and State of Massachusetts, said TURNER and 'DUNBAR residing at \Vorcester, county of -Worcester, and State of Massachusetts, have invented a new and useful Feeding Device for Grinding-Machines, of which the following is a specification.

This invention relates to an improved ratchet feeding device capable of general 'application'but more particularly designed gitudinally movable work carriage. .As the carriage approaches the end of'its travel in either direction thelever is reversed by one of the dogs and each movement of the "lever in either direction operates the cross .feed to move the grinding wheel toward the work.

It is the general object of our invention to improve the ratchet feeding devices through which the reversing lever is connected tomove the. grinding wheel transversely. I I I v In the previous commercial form, as more clearlyshOwn in the patent to Spence, a. .ratchet wheel was provided \vhlch was actu ated by a feed pawl which continually en- .gag'ed the ratchet wheel during both its operative and inoperative movements. Such engagement of the feed pawl with the wheel during the idle or backward stroke caused the pawl to drag overthe teeth of the wheel,

thereby causing excessive and useless wear of the teeth and pawl.

Accordingly one of the pr1ncipal features of our invention relates to the provision of *means for causing the feed pawl to perform its idle or backward stroke out of contact with the ratchet wheel.

Other features of our invcntlonrelate to Speciflcation'ot Letters Patent. Sept. 12, 19 16. Application filed June 28,1915. Serial No. 36,780. I

' certain devioes,..arrang'ements' and combinations of parts which will be hereinafter described and more particularly pointed out ingmachine with our improved feeding-device mounted thereon; Fig. 2 is an enlarged sectional view taken substantially'along the axes of the cross feed screw and the ratchet different position, and F ig, 6 is a plan viewof the hand feeding device taken in the .directlon of the arrow 6 in Fig. 3, certain parts'being shown in section.

Referring to Fig. '1', our invention is shown in connection with a-machine in .whlch the work carriage 10 1s longitudinally movable-and has mounted thereon adjustable dogs 11 and 12. As the carriage 1on preaches the end of its travel in either direction one or the dogs 11 or 12 contacts with a'reversing lever 13 mounted to turn about a pivot 14. A curved arm 15 is rigidly secured to the lever 13 and is movable therewith. A sleeve .16v is adjustably mounted upon the arm 15 and a, rack 17 is pivotally connected to an extension of the "sleeve 16. The rack 17 engages a pinion 18 pivoted upon a stud 19 and secured to a disk20 provided with a-crank-pin21. The .parts are so proportioned that the angular movement imparted to the reversing lever '13 by the dogs 11 or 12 will move the rack 17 in one direction or theother a distance sufficient to partially rotate the pinion-18 and the crank pin disk 20 connected thereto.

-. The extent of this partial rotation may be regulated by adjusting the sleeve 16 along the'curved arm 15 toward oraway .from the pivot 14. The ratchet wheel 22 is loosely mounted upon a fixed stud-23 (F ig. 2 and has fixed thereto a pinion 24 meshing with a gear 25 mounted on the cross feed screw 26. -T he screw 26 engages a threaded nut 27 mounted below the grinding wheel carriage 28. The parts thus far described form no part of our present invention and a more cen ers-dendrite thereof ..v iousl-.y mentiene Qur invention to the feeding devices through which angular movement of the crank pin 21 is ren-r .dered effective to rotate the ratchet wheel 22 and thesedevi-ces will now be describedf v" flketeiruifng -particularly to Figs. 3, 4 and 5 we provide a supporting a'rm 29 loosely mounted upon a sleeve 30 fixed to the frame g i lihejllmehine ,and concentric with the atjch \VJLQQLEQZQ: Inorderto provide a cer- :h stafnce to "the angular movement of 7 the 31-11129, a friction disk or spring washer '(Fig. 6} is provided which engages one side oftheliub of the arm-29 and forces. the huh agaii'ist a-rshoulder, 32 on the fixedsleeve 30 ;';.A;nu.t -33=is threaded on the sleeve and cons u-tesii means for forcing the friction gdi sk 113:1 against the huhpf the arm 29 with thewnecessary fricti'on'p'r": sure. A feed pawl lietFi-gi-3 )-is pivotally mounted upon a stud 3'';3I'6n the outer end of. the supporting ar'm 2 9 and is connected by a link 36 to the crank p-in21. A tooth 37 of hardened steel or other durable material is provided near the outerend of "the feed pawl 34 for engage- 3'fi""""in the end 'of the supporting-arm 29 provides a support for an angularly adjust- --al)"le cam-'38 h'a'ving ppositely disposed inelined fat'c'esas' clearly shown in Figs. 3 and 5. plunger 39 is mounted to slide longi- "34, said plunger belng prov ded with crutable cam-engaging surfaces at its lower end.

Rotation of the plunger is'prevented by a n: serenkey TLO (Fig. 3) projecting into a key- 40 ii'av 41 formed in,one 'side of the plunger and a s'pring'afl-mounted in the recess in the arifh3atforce's the plunger 39 into yielding engagement with the cam 38. r

The normal; position of the parts is shown 46 iii. F 5, theitooth 37 being outof engagement with the ratchet wheel-""22 and the plunger 39 engaging the right hand surface W'iththe'parts in this pos'ition the movement ofthe work carriage 1O of the cam 38.

will be toward the/right until the dog 11 engages the reversinglever 13,- such engagement causing a movement of-the rack 17 to- \iard the. left as viewed in Fig; 3. This mo 'enien 6f the rack 17 will move thecrank show in Fig. 5 to the dotted line position ZR-"in the same figure. This movement ofjhe-crank pin causes a movement of the link "3G downward followed by a corresponding .60 upward movement, .As the link moves d wnward the friction pressure upon the arm 29 retards the movement of the arm and;:the feedxpawl 34 swings freely about its pivot 35 until it engages the ratchetyvheel 22; by which engagement further swmgmg as is found a I inthe patents to Norton and Spence pro-m relatesmore particularly lower center the link'36 .ment with the ratchet wheel'22. The stud be moved into orout oi tudi'nall-y'in' recess formed in the feed pawl 21. :1 a circular path from the position to form a cam surface 57:

advancing the ratchet wheel" m"ined amount.

As. the crank dotted lines in Fig. 5, theibpenativewteeding' stroke only being per ormed-wrt in engagement Wit '1 eii ratche There is therefore no ragg ingzgo 37 over the teeth of thetwrhelznnd of these parts i-is practicallyel'iminiit For the: purpose of. 'ope'natirrg' the: cross feed manually a l audio-5Qfiisianounlieel upon a two-armed 1e r'"-5l--loosely pivot-e d upon the stud 23. -A "ts oppositev'e .d the. lever 51 is provided with apit rio it'ltih'h iiinay the ratchet wheel 22 -a" high began,- gularly'adjusted w'i t. 1;. if; thee-ev 51. The details ofthis'meclia is more clearly showjn i'n Fig. 1930i tI tent tor Norton, No. 672,838 toi-whichlxr degree is made for a full description?itiiereof f The lever 51 is also provided with"?a"shield 53;}; projectiiig laterally from the end of the 1e for and covering a portion. oh, the teeth of the ratchet wheel 22. ..-T lri'sg shifeldeiets to limit the automatic orossw'feed'iof ie gr'i'nding wheel, the feed contiiiu irrgj r 'l shield 53 is moved around-into aipdsit which it prevents the engagemen feed pawl tooth 37 with t-l" ratchet wheel 22.

It-is sometimes desirable; o

positive stop for the cros's' feed "where th'e same is being manually o1 )er'at ed. 'For this purpose we have provided a projecting p tion or stop 54 upon theeiid'oft'al At its left hand end this stop: with a substantially radial shou ltl ing a stud 56 projecting t-her'ef the opposite'end of ti'ie stopf When the stop is to b 16 is adjustedon ,the min 31" oted connection-to the-rack 1S'; fi i3l'ly alined' with the stud 14. The 'i ixiagement of the shoulder, 55 with theffsq'uare end of the d 'pawl 34 then positively prevents ovement-ofthe' lever:51.. The stud 139 56 at the same time enters a recess'58 in the end of the feed pawl and thus prevents the pawl from movingout of engagement with the stop 54.'

If the ratchet wheel 22 is rotated manually in the opposite directionto withdraw the wheel from the work the curved cam surface 57 will engage the pawl 34 and the tooth 37 and move them away from the wheel, thus permitting the stop 54 to pass freely thereunder.

It is sometimes desirable to cut out entirely the automatic cross feeding feature of the machine, which result is very simply attained in our construction by swinging the feed pawl 34 manually backward to the position i dicated in dotted lines at 34* in Fig.3. he plunger 39 then engages the left hand side of the cam 38 thus holding the feed pawl in the dotted line position.

-Having thus described our invention it willbe evident that changes and modifications can be made therein. without depart.- ing from the spirit and scope thereof as set forth in the claims and we do not wish to be limited to the details herein disclosed, but

What we do claim is:

1. In a grinding machine, a feeding device comprising a ratchet wheel, an arm pivoted concentrically therewith, a feed pawl pivoted to said arm, and means to cause the ratchetengaging portion of said pawl to move in a closedpath, with said pawl. in engagement with said wheel during its operative movement only.

2. In a grinding machine, a .feeding device comprising a ratchet Wheel, an arm pivoted concentric therewith, a feed pawl pivoted to said arm, and means to cause the ratchet-engaging portion of said pawl to engage and feed said ratchet wheel, to thereafter move said pawl away from said wheel, and to return said pawl to initial position while out of contact with said wheel.

3. In a grinding machine, a feeding device comprising a ratchet wheel, an arm pivoted concentric therewith, 'a feed pawl pivoted to said arm, and means for actuating said pawl, said arm being restrained from free movement by a friction-binder and said pawl having a limited free movement on said arm.

4. Ina grinding machine, a feeding device comprising a ratchet wheel, an arm pivoted concentric therewith, a feed pawl pivoted to said arm, and means for actuating free movement by said pawl, said arm being restrained from free movement by a friction binder and said pawl having a limited free movement,

' on said arm and being further movable manually to a wholly inoperative position.

5. In a grinding machine, a feedingdevice comprising a ratchet Wheel, an arm pivoted concentric therewith, a feed pawl pivoted to said arm, and means for actuating said pawl, said arm being restrained from a friction binder and said pawl carrying ayielding plunger effecitive to engage a fixed cam stop to limitthe fre movement of said pawl, said plunger being manually movable beyond said stop and thereafter engaging the opposite side of said stop to retain said pawl in .awholly in operative position.

6. In a grinding machine, in combination, a ratchet wheel, a feed pawl operable to ro.-' tate said wheel, a manually operable lever,

and means to adj ustably secure said lever to said wheel, said lever and pawl having engaging portions effective topositively limit movement of said lever toward 'said pawl in one relative movement of said lever inthe opposite direction.

7 In a grinding machine, in combination, a ratchet wheel a feed pawl operable to rotate said wheel, a manuallyoperable lever, and means to adjustably secure said lever to said wheel, said lever and pawl having engaging portions effective to positively limit movement of said lever toward said pawl in one direction, said engaging portions comprising abutting shoulders on said lever and pawl, and a stud on one part en'- gaging a recess in the other part and limit-' ing the outward movement of said pawl away from said ratchet wheel.

8. In a grinding machine, a feedingde vice comprising a ratchet wheel, a feed pawl for said wheel, means to give said pawl an operative movement in engagement with said wheel, and means to move said'pawl out of engagement with said wheel at the beginning of the idle return strokeand'to hold said pawl out of engagement with said wheel until the pawl is positioned to begin its next operative stroke.

In testimony whereof we have hereunto set our hands.

JOSEPH S. \VILCOX, JR.

ALBERT TURXER.

HOWARD V. DUNBAR.

direction, while permitting. free. 

